1 files changed, 137 insertions, 0 deletions
diff --git a/util/httpstream.lua b/util/httpstream.lua
new file mode 100644
index 00000000..bdc3fce7
--- /dev/null
+++ b/util/httpstream.lua
@@ -0,0 +1,137 @@
+
+local coroutine = coroutine;
+local tonumber = tonumber;
+
+local deadroutine = coroutine.create(function() end);
+coroutine.resume(deadroutine);
+
+module("httpstream")
+
+local function parser(success_cb, parser_type, options_cb)
+	local data = coroutine.yield();
+	local function readline()
+		local pos = data:find("\r\n", nil, true);
+		while not pos do
+			data = data..coroutine.yield();
+			pos = data:find("\r\n", nil, true);
+		end
+		local r = data:sub(1, pos-1);
+		data = data:sub(pos+2);
+		return r;
+	end
+	local function readlength(n)
+		while #data < n do
+			data = data..coroutine.yield();
+		end
+		local r = data:sub(1, n);
+		data = data:sub(n + 1);
+		return r;
+	end
+	local function readheaders()
+		local headers = {}; -- read headers
+		while true do
+			local line = readline();
+			if line == "" then break; end -- headers done
+			local key, val = line:match("^([^%s:]+): *(.*)$");
+			if not key then coroutine.yield("invalid-header-line"); end -- TODO handle multi-line and invalid headers
+			key = key:lower();
+			headers[key] = headers[key] and headers[key]..","..val or val;
+		end
+		return headers;
+	end
+	
+	if not parser_type or parser_type == "server" then
+		while true do
+			-- read status line
+			local status_line = readline();
+			local method, path, httpversion = status_line:match("^(%S+)%s+(%S+)%s+HTTP/(%S+)$");
+			if not method then coroutine.yield("invalid-status-line"); end
+			path = path:gsub("^//+", "/"); -- TODO parse url more
+			local headers = readheaders();
+			
+			-- read body
+			local len = tonumber(headers["content-length"]);
+			len = len or 0; -- TODO check for invalid len
+			local body = readlength(len);
+			
+			success_cb({
+				method = method;
+				path = path;
+				httpversion = httpversion;
+				headers = headers;
+				body = body;
+			});
+		end
+	elseif parser_type == "client" then
+		while true do
+			-- read status line
+			local status_line = readline();
+			local httpversion, status_code, reason_phrase = status_line:match("^HTTP/(%S+)%s+(%d%d%d)%s+(.*)$");
+			status_code = tonumber(status_code);
+			if not status_code then coroutine.yield("invalid-status-line"); end
+			local headers = readheaders();
+			
+			-- read body
+			local have_body = not
+				 ( (options_cb and options_cb().method == "HEAD")
+				or (status_code == 204 or status_code == 304 or status_code == 301)
+				or (status_code >= 100 and status_code < 200) );
+			
+			local body;
+			if have_body then
+				local len = tonumber(headers["content-length"]);
+				if headers["transfer-encoding"] == "chunked" then
+					body = "";
+					while true do
+						local chunk_size = readline():match("^%x+");
+						if not chunk_size then coroutine.yield("invalid-chunk-size"); end
+						chunk_size = tonumber(chunk_size, 16)
+						if chunk_size == 0 then break; end
+						body = body..readlength(chunk_size);
+						if readline() ~= "" then coroutine.yield("invalid-chunk-ending"); end
+					end
+					local trailers = readheaders();
+				elseif len then -- TODO check for invalid len
+					body = readlength(len);
+				else -- read to end
+					repeat
+						local newdata = coroutine.yield();
+						data = data..newdata;
+					until newdata == "";
+					body, data = data, "";
+				end
+			end
+			
+			success_cb({
+				code = status_code;
+				httpversion = httpversion;
+				headers = headers;
+				body = body;
+				-- COMPAT the properties below are deprecated
+				responseversion = httpversion;
+				responseheaders = headers;
+			});
+		end
+	else coroutine.yield("unknown-parser-type"); end
+end
+
+function new(success_cb, error_cb, parser_type, options_cb)
+	local co = coroutine.create(parser);
+	coroutine.resume(co, success_cb, parser_type, options_cb)
+	return {
+		feed = function(self, data)
+			if not data then
+				if parser_type == "client" then coroutine.resume(co, ""); end
+				co = deadroutine;
+				return error_cb();
+			end
+			local success, result = coroutine.resume(co, data);
+			if result then
+				co = deadroutine;
+				return error_cb(result);
+			end
+		end;
+	};
+end
+
+return _M;